Emulex EMULEX User Manual

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FCA Utilities Reference Manual
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Introduction 
This document provides the information needed to use the Emulex® emlxadm and elmxdrv utility 
programs. For system administrators, this document includes information about the installation and 
removal of these utilities.
At the very least, system administrators should be familiar with Solaris and the Sun StorEdge SAN 
Foundation Software (SFS) and should have access to standard system documentation. Anyone 
working with this product should have some familiarity with the nature and use of Fibre Channel.
Fibre Channel Overview
Fibre Channel is a general-purpose, high-throughput, low-latency interconnect. It employs serial bit 
transmission over copper media, short-wave and long-wave optical media. Cable distances may range 
up to 30 meters for copper media and up to 10 kilometers for optical media. Transmission speeds 
currently range up to 4 gigabits per second, or roughly 400 megabytes per second. Fibre Channel 
transmission protocols provide high reliability, with bit error rates less than 1 in 10
-12
. Interconnects may 
be configured as point-to-point, loop, or fabric (network switch).
The Fibre Channel specifications provide for the emulation of two traditional protocols: SCSI and IP. For 
storage, Fibre Channel provides an emulation of SCSI; this emulation is dubbed FCP, short for Fibre 
Channel Protocol
 – a confusing acronym, in that it refers specifically to SCSI-on-Fibre Channel rather 
than to the lower-level protocols by which Fibre Channel itself operates. Throughout this document, we 
generally refer to FCP; when we mention SCSI, we are referring to the particular SCSI properties within 
FCP, or to the original SCSI protocol. For networking, Fibre Channel provides an encapsulation of IP 
(Internet Protocol), referred to in this document as IP.
The Solaris Fibre Channel Stack
Each Fibre Channel host bus adapter (HBA) is managed by an associated device driver. A device driver 
acts as a translator between an operating system and the hardware so that the operating system's 
kernel need not know the specifics of the device it uses. A device driver contains all of the code specific 
to operating a device and provides an input/output (I/O) interface to the rest of the system.
The Emulex-Sun LightPulse® HBA device driver for Solaris, emlxs, is a Fibre Channel adapter (FCA) 
driver as specified by the Sun Fibre Channel architecture (also known as Leadville). The heart of the 
Sun Fibre Channel architecture consists of the Fibre Channel transport layer (FCTL) modules, which 
provide a common interface for various Fibre Channel adapters on a host. These modules consist of 
several tightly coupled pieces, including a per-port driver (FP) and a system-wide transport layer (FCTL) 
driver. The FP driver handles all per-port state and common services needed by a variety of protocols 
and the FCA drivers. The FCTL module provides consistent, system-wide access of Fibre Channel 
devices and services to upper layer protocols (ULP) and administration utilities. The point of providing a 
Fibre Channel port/transport interface is to abstract and define all services available through an FCA 
driver needed by FC-4 ULP drivers such as the SCSI driver (FCP) and the IP driver (FCIP). The FCP 
function provides access to Fibre Channel disk and tape drives. The IP function provides peer-to-peer 
networking, such as TCP or UDP, between Fibre Channel hosts.